1. Field of the Invention
This invention relates to a crane upperstructure self-transferring system. More specifically, the invention is directed to a system that does not need an auxiliary crane for transferring a crane upperstructure between a carrier that is used for traveling to a job site and a transport vehicle that is used for long-haul traveling between job sites.
2. Description of the Prior Art
Because of the size and weight of large cranes, it is often necessary to disassemble the cranes to transport them from one job site to another. Such disassembly is accomplished by removing the crane upperstructure from the crane lowerstructure or carrier on the job site. The crane upperstructure is then transferred to a vehicle for transport between job sites. Upon arriving at the new job site, it is necessary to transfer the crane upperstructure from the transport back to the carrier. Such transferring of the crane upperstructure can be done with an auxiliary crane, but sometimes the only crane at a job site will be the crane to be transferred. Thus, a self-transferring system is needed for the crane upperstructure.
U.S. Pat. No. 3,923,407 that issued on Dec. 2, 1975, to Jensen et al shows a mechanism for connecting and disconnecting crane sections. Removable jacks are shown for raising or lowering a crane upper section above a base section. There is no disclosure as to how the jacks are positioned or connected relative to the crane upper section. U.S. Pat. No. 3,921,817 that issued on Nov. 25, 1975, to Petrik et al shows another mechanism for connecting and disconnecting crane sections.
U.S. Pat. No. 2,958,508, that issued on Nov. 1, 1960, to Martinez, shows a device for lifting a heavy equipment body above a tractor with jacks and cross-beams. A pair of U-bolts that are fitted upon one cross-beam engage pins at the front end of the body, and a pair of bracket arms that are fitted upon the other cross-beam engage the rear end of the body.
U.S. Pat. No. 3,191,706, that issued on June 29, 1965, to Petersen, shows a vertical jack that is supported by a tripod. Air pads are located at the base of each leg of the tripod. These air pads enable the jack to be moved laterally over uneven ground for aligning the jack on a vertical line beneath a lifting pad on an aircraft to be weighed.
U.S. Pat. No. 3,638,805, that issued on Feb. 1, 1972, to Garnier, shows a mobile chassis for carrying a tower crane. Outrigger supports are pivotally mounted to the crane frame. These supports are pivoted inward towards the frame so that the crane can be legally moved over a highway. At a job site, the outrigger supports are pivoted outward to a fully extended position providing maximum support against overturning forces on the crane.
U.S. Pat. Nos. 3,840,125, that issued on Oct. 8, 1974, to Cozad, and 4,014,519, that issued on Mar. 29, 1977, to Leigh, show outrigger jacks mounted on a carrier for a truck crane. U.S. Pat. No. 3,375,048, that issued on Mar. 26, 1968, to Korensky et al, shows a counterweight mounting mechanism, U.S. Pat. No. 4,018,473, that issued on Apr. 19, 1977, to Chalupsky, shows a crane operator's cab that can be raised and lowered.